1. Field of the Invention
The present invention relates to an engine room structure of an automotive vehicle and, more particularly, to such an engine room structure of the automotive vehicle as capable of disposing a pair of left-hand and right-hand front side frames with a high freedom of disposition in the vertical direction of the vehicle body within the engine room.
2. Description of Related Art
Japanese Utility Model Laid-open Publication No. 47,483/1989 discloses the structure of an engine room in which a pair of left-hand and right-hand front side frames extending in the longitudinal direction of the vehicle body are disposed on the respective side walls of the engine defined by and divided from the vehicle chamber by the dash panel. It is common that the engine unit or the front wheel suspension unit is loaded directly or indirectly on the front side frames.
It is to be noted, however, that for the front-wheel drive vehicle in which at least the front wheels are driven or for the four-wheel drive vehicle in which the rear wheels are driven as well as the front wheels, a power transmission mechanism for transmitting the power to the front wheels is disposed in the engine room. More specifically, a front axle is so disposed as to extend from the engine unit interposed between the left-hand and right-hand front side frames toward the outside in the transverse direction of the vehicle body and so to associate with the left-hand and right-hand front wheels, respectively, through a universal joint. It is noted as a matter of course that the engine room is provided with a front-wheel steering mechanism to steer the front wheels to the left or to the right by means of a steering wheel disposed at the driver's seat.
Therefore, it can be noted that the automotive vehicle in which at least the front wheels are to be driven is provided within the engine room with a front axle as a member extending and bridging between the left-hand and right-hand front wheels in the transverse direction of the vehicle body and with a steering rack as an element of the front-wheel steering mechanism. Description on disposition of the front axle and steering rack for the conventional automotive vehicle will be described hereinafter with reference to FIG. 14.
As shown in FIG. 14, reference numeral 100 denotes an engine room and reference numeral 102 denotes a vehicle chamber, and the engine room 100 and the vehicle chamber 102 are defined and divided by a dash panel 104. The engine 106 loaded in the engine room 100 is provided with a transmission unit 108 at its side in the transverse direction of the vehicle body, for example, in case of the engine to be so loaded as for its output shaft to lie in the transverse direction of the vehicle body. To the rear end of the transmission unit 108 is connected a power transmission member 110 from which the front axle 112 is disposed to extend toward the outside in the transverse direction of the vehicle body.
For the conventional system, the steering rack 114 functioning as one element of the front-wheel steering mechanism is located above the power transmission unit 110. The conventional position of disposition of the steering rack 114 is indicated by the solid line as shown in FIG. 14. It is therefore necessary from the viewpoint of designing the vehicle body to dispose the front side frame 116 at the height so as to avoid interference with the steering rack 114.